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Full-Text Articles in Physical Sciences and Mathematics
Shear Turbulence In The High-Wind Southern Ocean Using Direct Measurements, Laur Ferris, Carole Anne Clayson, Donglai Gong, Et Al
Shear Turbulence In The High-Wind Southern Ocean Using Direct Measurements, Laur Ferris, Carole Anne Clayson, Donglai Gong, Et Al
VIMS Articles
The ocean surface boundary layer is a gateway of energy transfer into the ocean. Wind-driven shear and meteorologically forced convection inject turbulent kinetic energy into the surface boundary layer, mixing the upper ocean and transforming its density structure. In the absence of direct observations or the capability to resolve sub-grid scale 3D turbulence in operational ocean models, the oceanography community relies on surface boundary layer similarity scalings (BLS) of shear and convective turbulence to represent this mixing. Despite their importance, near-surface mixing processes (and ubiquitous BLS representations of these processes) have been under-sampled in high energy forcing regimes such as …
Wind-Modulated Western Maine Coastal Current And Its Connectivity With The Eastern Maine Coastal Current, Denghui Li, Zhengui Wang, Huijie Xue, Andrew C. Thomas, Ron J. Etter
Wind-Modulated Western Maine Coastal Current And Its Connectivity With The Eastern Maine Coastal Current, Denghui Li, Zhengui Wang, Huijie Xue, Andrew C. Thomas, Ron J. Etter
VIMS Articles
Using a high-resolution circulation model and an offline particle tracking model, we investigated variations of the Western Maine Coastal Current (WMCC) and its connectivity with the Eastern Maine Coastal Current (EMCC). The models showed that the weak, broad, and sinuous WMCC is generally southwestward with an offshore and a nearshore core, fed by the extension of the EMCC and runoff from the Penobscot and Kennebec–Androscoggin Rivers, respectively. A sea-level dome can form offshore of Casco Bay in late fall and early winter as the northeastward alongshore wind sets up a seaward sea-level gradient from the coast to meet the shoreward …
A General Pattern Of Trade-Offs Between Ecosystem Resistance And Resilience To Tropical Cyclones, Christopher J. Patrick, John S. Kominoski, (...), Enie Hensel, Marc J. S. Hense, Bradley A. Strickland, (..), A. K. Hardison, Sean Kinard, Et Al
A General Pattern Of Trade-Offs Between Ecosystem Resistance And Resilience To Tropical Cyclones, Christopher J. Patrick, John S. Kominoski, (...), Enie Hensel, Marc J. S. Hense, Bradley A. Strickland, (..), A. K. Hardison, Sean Kinard, Et Al
VIMS Articles
Tropical cyclones drive coastal ecosystem dynamics, and their frequency, intensity, and spatial distribution are pre-dicted to shift with climate change. Patterns of resistance and resilience were synthesized for 4138 ecosystem time series from n = 26 storms occurring between 1985 and 2018 in the Northern Hemisphere to predict how coastal ecosystems will respond to future disturbance regimes. Data were grouped by ecosystems (fresh water, salt water, terrestrial, and wetland) and response categories (biogeochemistry, hydrography, mobile biota, sedentary fauna, and vascular plants). We observed a repeated pattern of trade-offs between resistance and resilience across analyses. These patterns are likely the outcomes …
Controls On Sediment Bed Erodibility In A Muddy, Partially-Mixed Tidal Estuary, Cristin L. Wright, Carl T. Friedrichs, Grace M. Massey
Controls On Sediment Bed Erodibility In A Muddy, Partially-Mixed Tidal Estuary, Cristin L. Wright, Carl T. Friedrichs, Grace M. Massey
VIMS Articles
he objectives of this study are to better understand controls on bed erodibility in muddy estuaries, including the roles of both sediment properties and recent hydrodynamic history. An extensive data set of erodibility measurements, sediment properties, and hydrodynamic information was utilized to create statistical models to predict the erodibility of the sediment bed. This data set includes >160 eroded mass versus applied stress profiles collected over 15 years along the York River estuary, a system characterized by “depth-limited erosion,” such that the critical stress for erosion increases rapidly with depth into the bed. For this study, erodibility was quantified in …
Primary Productivity In The Mid-Atlantic Bight: Is The Shelf Break A Location Of Enhanced Productivity?, Jiejie Ma, Walker O. Smith Jr.
Primary Productivity In The Mid-Atlantic Bight: Is The Shelf Break A Location Of Enhanced Productivity?, Jiejie Ma, Walker O. Smith Jr.
VIMS Articles
Estimates of primary production represent the input of carbon into food webs, as well as the initial step in the biological pump. For the past 60 years, much of the productivity information has been obtained using measurements of 14C-bicarbonate removal during simulated in situ incubations. However, such measurements often do not reflect the complexity of the environment, and also suffer from uncertainties, biases and limitations. A vertically resolved bio-optical model has been used to estimate productivity based on profiles commonly assessed in oceanographic investigations, but comparisons with simultaneous measurements of 14C-uptake are limited. We conducted three cruises off the coast …
Benthic Biofilm Potential For Organic Carbon Accumulation In Salt Marsh Sediments, Kendall Valentine, Abbey Hotard, Tracy Elsey-Quirk, Giulio Mariotti
Benthic Biofilm Potential For Organic Carbon Accumulation In Salt Marsh Sediments, Kendall Valentine, Abbey Hotard, Tracy Elsey-Quirk, Giulio Mariotti
VIMS Articles
Coastal salt marshes are productive environments with high potential for carbon accumulation and storage. Even though organic carbon in salt marsh sediment is typically attributed to plant biomass, it can also be produced by benthic photosynthetic biofilms. These biofilms, generally composed of diatoms and their secretions, are known for their high primary productivity and contribution to the basal food web. The growth of biofilms and the preservation of carbon produced by biofilms depends on the amount of sedimentation; low sedimentation rates will favor decomposition, while high sedimentation rates could decrease biofilm productivity. In this study, we conducted laboratory experiments to …
Uncrewed Ocean Gliders And Saildrones Support Hurricane Forecasting And Research, Travis N. Miles, Dongxiao Zhang, Gregory R. Foltz, (...), Donglai Gong, Et Al
Uncrewed Ocean Gliders And Saildrones Support Hurricane Forecasting And Research, Travis N. Miles, Dongxiao Zhang, Gregory R. Foltz, (...), Donglai Gong, Et Al
VIMS Articles
In the United States alone, hurricanes have been responsible for thousands of deaths and over US$1 trillion in damages since 1980 (https://www.ncdc.noaa.gov/billions/). These impacts are significantly greater globally, particularly in regions with limited hurricane early warning systems and where large portions of the population live at or near sea level. The high socioeconomic impacts of tropical cyclones will increase with a changing climate, rising sea level, and increasing coastal populations. To mitigate these impacts, efforts are underway to improve hurricane track and intensity forecasts, which drive storm surge models and evacuation orders and guide coastal preparations. Hurricane track forecasts have …
Adcp Observations Of Currents And Suspended Sediment In The Macrotidal Gulf Of Martaban, Myanmar, Courtney K. Harris, Jacob T. Wacht, Matthew J. Fair, Jessica M. Cote
Adcp Observations Of Currents And Suspended Sediment In The Macrotidal Gulf Of Martaban, Myanmar, Courtney K. Harris, Jacob T. Wacht, Matthew J. Fair, Jessica M. Cote
VIMS Articles
The Ayeyarwady and Thanlwin Rivers, which drain Myanmar, together form one of the largest point sources of freshwater and sediment to the global ocean. Combined, these rivers annually deliver an estimated 485 Mt of sediment to the northern Andaman Sea. This sediment contributes to a perennially muddy zone within the macro-tidal Gulf of Martaban, but little is known about the processes that dominate dispersal and trapping of sediment there, as very few water column observations are available. A research cruise in December 2017 provided a rare opportunity to obtain Acoustic Doppler Current Profiler (ADCP) data along transects from the Gulf …
Measuring Organization Of Large Surficial Clasts In Heterogeneous Gravel Beach Sediments, Dennis C. Lees, Christopher J. Hein, Duncan M. Fitzgerald
Measuring Organization Of Large Surficial Clasts In Heterogeneous Gravel Beach Sediments, Dennis C. Lees, Christopher J. Hein, Duncan M. Fitzgerald
VIMS Articles
The natural stratification and interlocking “organization” of armored sediments in heterogeneous, coarse-grained, beaches provides protection and enhances habitat for borrowing sedentary megafauna and macrofauna such as hard-shelled clams. Here, we develop a novel metric for quantifying sediment organization of large surficial beach clasts through sedimentologic and photogrammetric analyses of 37 lower intertidal heterogeneous gravel beaches in western Prince William Sound, Alaska (USA). Grain size, photogrammetric, and Wolman Pebble Count clast-size data from 64, ~1-m2 study plots are combined into a clast-size-independent “Organization Metric” to quantify the degree of organization in the meshed arrangement of larger surficial sediments. This metric …
Variability In Marsh Migration Potential Determined By Topographicrather Than Anthropogenic Constraints In The Chesapeake Bay Region, Grace D. Molino, Joel A. Carr, Neil K. Ganju, Matthew L. Kirwan
Variability In Marsh Migration Potential Determined By Topographicrather Than Anthropogenic Constraints In The Chesapeake Bay Region, Grace D. Molino, Joel A. Carr, Neil K. Ganju, Matthew L. Kirwan
VIMS Articles
Sea level rise (SLR) and saltwater intrusion are driving inland shifts in coastal ecosystems. Here, we make high-resolution (1 m) predictions of land conversion under future SLR scenarios in 81 watersheds surrounding Chesapeake Bay, United States, a hotspot for accelerated SLR and saltwater intrusion. We find that 1050–3748 km2 of marsh could be created by 2100, largely at the expense of forested wetlands. Predicted marsh migration exceeds total current tidal marsh area and is about 4x greater than historical observations. Anthropogenic land use in marsh migration areas is concentrated within a few watersheds and minimally impacts calculated metrics of marsh …
Contamination Of Finescale Strain Estimates Of Turbulent Kinetic Energy Dissipation By Frontal Physics, Laur Ferris, Donglai Gong, Sophia Merrifield, Louis St. Laurent
Contamination Of Finescale Strain Estimates Of Turbulent Kinetic Energy Dissipation By Frontal Physics, Laur Ferris, Donglai Gong, Sophia Merrifield, Louis St. Laurent
VIMS Articles
Finescale strain parameterization (FSP) of turbulent kinetic energy dissipation rate has become a widely used method for observing ocean mixing, solving a coverage problem where direct turbulence measurements are absent but CTD profiles are available. This method can offer significant value, but there are limitations in its broad application to the global ocean. FSP often fails to produce reliable results in frontal zones where temperature–salinity (T/S) intrusive features contaminate the CTD strain spectrum, as well as where the aspect ratio of the internal wave spectrum is known to vary greatly with depth, as frequently occurs in …
Effects Of Shell Hash On Friction Angles Of Surficial Seafloor Sediments Near Oysters, Samuel T. Consolvo, Nina Stark, (...), Grace M. Massey
Effects Of Shell Hash On Friction Angles Of Surficial Seafloor Sediments Near Oysters, Samuel T. Consolvo, Nina Stark, (...), Grace M. Massey
VIMS Articles
Oysters are hypothesized to affect the shear strength of nearby surficial seafloor sediment as fragments of oyster shells (shell hash) are typically more angular relative to sand particles alone, among other differences. Resistance to shearing is well characterized by the friction angle, which is estimated in this study from vacuum triaxial laboratory and portable free-fall penetrometer field tests. Friction angles of sediment with shell hash were higher relative to those of sediment without shell hash (via hydrochloric acid treatment) on average by about 19% (36.0°–30.2°, respectively). Triaxial confining pressures ranged between 2.1 and 49.0 kPa to simulate subtidal and intertidal …
Surface Chlorophyll Anomalies Induced By Mesoscale Eddy-Wind Interactions In The Northern Norwegian Sea, Huizi Dong, Meng Zhou, Roshin P. Raj, Walker O. Smith Jr., Et Al
Surface Chlorophyll Anomalies Induced By Mesoscale Eddy-Wind Interactions In The Northern Norwegian Sea, Huizi Dong, Meng Zhou, Roshin P. Raj, Walker O. Smith Jr., Et Al
VIMS Articles
The substantial productivity of the northern Norwegian Sea is closely related to its strong mesoscale eddy activity, but how eddies affect phytoplankton biomass levels in the upper ocean through horizontal and vertical transport-mixing has not been well quantified. To assess mesoscale eddy induced ocean surface chlorophyll-a concentration (CHL) anomalies and modulation of eddy-wind interactions in the region, we constructed composite averaged CHL and wind anomalies from 3,841 snapshots of anticyclonic eddies (ACEs) and 2,727 snapshots of cyclonic eddies (CEs) over the period 2000-2020 using satellite altimetry, scatterometry, and ocean color products. Results indicate that eddy pumping induces negative (positive) CHL …
A Multi-Decadal Analysis Of River Discharge And Suspended Sediment Load In Three Texas Coastal Rivers In Relation To Hurricanes, Seasonal Rainfall, And Enso, Qiang Yao, Sanjeev Joshi, Kam-Biu Liu, Erika Rodrigues, Dongxiao Yin
A Multi-Decadal Analysis Of River Discharge And Suspended Sediment Load In Three Texas Coastal Rivers In Relation To Hurricanes, Seasonal Rainfall, And Enso, Qiang Yao, Sanjeev Joshi, Kam-Biu Liu, Erika Rodrigues, Dongxiao Yin
VIMS Articles
Coastal river discharge and sediment load exert major influence on the sustainability of coastal systems. Controlled by various hydroclimatic/hydrometeorological agents, they exhibit distinct trend/variability at different time scales. Coastal Texas, while being a major target for tropical cyclones over the past 6 decades, has been experiencing drought and flood cycles associated with ENSO in the long term. However, it is still unclear the temporal variability of river discharge and the associated sediment delivery over this area at different time scales, and the controlling factors behind it. In this study, a 58-years (1960–2017) dataset is compiled to analyze the influence of …
Primary Productivity Measurements In The Ross Sea, Antarctica: A Regional Synthesis, Walker O. Smith Jr.
Primary Productivity Measurements In The Ross Sea, Antarctica: A Regional Synthesis, Walker O. Smith Jr.
VIMS Articles
Polar systems are undersampled due to the difficulty of sampling remote and challenging environments; however, these systems are critical components of global biogeochemical cycles. Measurements on primary productivity in specific areas can quantify the input of organic matter to food webs and so are of critical ecological importance as well. However, long-term measurements using the same methodology are available only for a few polar systems. Primary productivity measurements using 14C-uptake incubations from the Ross Sea, Antarctica, are synthesized, along with chlorophyll concentrations at the same depths and locations. A total of 19 independent cruises were completed and 449 stations …
Clarifying Water Clarity: A Call To Use Metrics Best Suited To Corresponding Research And Management Goals In Aquatic Ecosystems, Jessica S. Turner, Kelsey A. Fall, Carl T. Friedrichs
Clarifying Water Clarity: A Call To Use Metrics Best Suited To Corresponding Research And Management Goals In Aquatic Ecosystems, Jessica S. Turner, Kelsey A. Fall, Carl T. Friedrichs
VIMS Articles
Water clarity is a subjective term and can be measured multiple ways. Different metrics such as light attenuation and Secchi depth vary in effectiveness depending on the research or management application. In this essay, we argue that different questions merit different water clarity metrics. In coastal and inland waters, empirical relationships to estimate light attenuation can yield clarity estimates that either under- or overestimate the underwater light climate for restoration goals, such as potential habitat available for submerged aquatic vegetation. Best practices in reporting water clarity measurements include regionally specific, temporally representative calibrations and communicating the metric that was actually …
Nutrient Function Over Form: Organic And Inorganic Nitrogen Additions Have Similar Effects On Lake Phytoplankton Nutrient Limitation, Sabrina N. Volponi, Heather L. Wander, (...), Brian S. Kim, Et Al
Nutrient Function Over Form: Organic And Inorganic Nitrogen Additions Have Similar Effects On Lake Phytoplankton Nutrient Limitation, Sabrina N. Volponi, Heather L. Wander, (...), Brian S. Kim, Et Al
VIMS Articles
The concentration of dissolved organic nitrogen (DON) is increasing in many northern hemisphere lakes, yet its use by phytoplankton and fate in the environment seldom have been quantified. We conducted 1 week, insitu, microcosm incubations across 25 lakes in northeastern North America to understand how DON, dissolved norganic nitrogen (DIN), and dissolved inorganic phosphorus (P) affected phytoplankton biomass. In addition,we tested whether lakes were limited by single macronutrients (N or P) or colimited by both. Phytoplankton biomass in 80% of lakes responded similarly to DON and DIN additions. Of the lakes where N form produced differential responses, the majority of …
Marine Heatwaves In The Chesapeake Bay, Piero L. F. Mazzini, Cassia Pianca
Marine Heatwaves In The Chesapeake Bay, Piero L. F. Mazzini, Cassia Pianca
VIMS Articles
Prolonged events of anomalously warm sea water temperature, or marine heatwaves (MHWs), have major detrimental effects to marine ecosystems and the world's economy. While frequency, duration and intensity of MHWs have been observed to increase in the global oceans, little is known about their potential occurrence and variability in estuarine systems due to limited data in these environments. In the present study we analyzed a novel data set with over three decades of continuous in situ temperature records to investigate MHWs in the largest and most productive estuary in the US: the Chesapeake Bay. MHWs occurred on average twice per …
Reconciling Models And Measurements Of Marsh Vulnerability To Sealevel Rise, Daniel J. Coleman, Mark Schuerch, (...), Matthew L. Kirwan
Reconciling Models And Measurements Of Marsh Vulnerability To Sealevel Rise, Daniel J. Coleman, Mark Schuerch, (...), Matthew L. Kirwan
VIMS Articles
Tidal marsh survival in the face of sea level rise (SLR) anddeclining sediment supply often depends on the ability ofmarshes to build soil vertically. However, numerical models typically predict survival under rates of SLR that farexceedfield-based measurements of vertical accretion. Here, we combine novel measurements from sevenU.S. Atlantic Coast marshes and data from 70 additional marshes from around the world to illustrate that—over con-tinental scales—70% of variability in marsh accretion rates can be explained by suspended sediment concentratin(SSC) and spring tidal range (TR). Apparent discrepancies between models and measurements can be explained bydiffering responses in high marshes and low marshes,the …
Ephemeral Surface Chlorophyll Enhancement At The New England Shelf Break Driven By Ekman Restratification, H. Oliver, W. G. Zhang, K. M. Hirzel, Walker O. Smith Jr., Et Al
Ephemeral Surface Chlorophyll Enhancement At The New England Shelf Break Driven By Ekman Restratification, H. Oliver, W. G. Zhang, K. M. Hirzel, Walker O. Smith Jr., Et Al
VIMS Articles
The Mid-Atlantic Bight (MAB) hosts a large and productive marine ecosystem supported by high phytoplankton concentrations. Enhanced surface chlorophyll concentrations at the MAB shelf-break front have been detected in synoptic measurements, yet this feature is not present in seasonal means. To understand why, we assess the conditions associated with enhanced surface chlorophyll at the shelf break. We employ in-situ and remote sensing data, and a 2-dimensional model to show that Ekman restratification driven by upfront winds drives ephemerally enhanced chlorophyll concentrations at the shelf-break front in spring. Using 8-day composite satellite-measured surface chlorophyll concentration data from 2003–2020, we constructed a …
Simple Relationships Between Residence Time And Annual Nutrient Retention, Export, And Loading For Estuaries, Jian Shen, Jiabi Du, Lisa V. Lucas
Simple Relationships Between Residence Time And Annual Nutrient Retention, Export, And Loading For Estuaries, Jian Shen, Jiabi Du, Lisa V. Lucas
VIMS Articles
Simple mathematical models are derived from mass balances for water and transported substance to provide insight into the relationships between import, export, transport, and internal removal for nonconservative sub-stances in an estuary. Extending previous work, our models explicitly include water and substance inputs from the ocean and are expressed in terms of timescales (i.e., mean residence time and the timescale for net removal). Steady-state, timescale-based expressions for ratios of export to import, retention to import, and net export to loading, as well as for loading and annually averaged concentration, are provided. The net export:loading model explains the underlying mechanisms for …
Sediment And Terrestrial Organic Carbon Budgets For The Offshore Ayeyarwady Delta, Myanmar: Establishing A Baseline For Future Change, Evan R. Flynn, S. Kuehl, Courtney K. Harris, Matthew J. Fair
Sediment And Terrestrial Organic Carbon Budgets For The Offshore Ayeyarwady Delta, Myanmar: Establishing A Baseline For Future Change, Evan R. Flynn, S. Kuehl, Courtney K. Harris, Matthew J. Fair
VIMS Articles
Large river deltas serve as globally important archives of terrestrial and shallow marine biogeochemical signatures and because of rapid sedimentation have the potential to impact global biogeochemical cycling. The Ayeyarwady Delta in Myanmar ranks as the world's third largest river delta in terms of sediment supply; however, modern increases in regional anthropogenic impacts risk severe alteration to sediment and TerrOC loads within this major system. By investigating modern sediment and terrestrial organic carbon (TerrOC) accumulation within the offshore Ayeyarwady Delta this study estimates baseline sediment and TerrOC budgets for this understudied mega-delta. Using 210Pb geochronology of 27 sediment cores collected …
Multi-Biomarker Analysis For Identifying Organic Matter Sources In Small Mountainous River Watersheds: A Case Study Of The Yuba River Watershed, Christina R. Pondell, Elizabeth A. Canuel
Multi-Biomarker Analysis For Identifying Organic Matter Sources In Small Mountainous River Watersheds: A Case Study Of The Yuba River Watershed, Christina R. Pondell, Elizabeth A. Canuel
VIMS Articles
Organic matter in soils and sediments derives from a mixture of biological origins, often making it difficult to determine inputs from individual sources. Complicating the determination of source inputs to soil and sedimentary organic matter (OM) is the fact that physical and microbial processes have likely modified the initial composition of these sources. This study focused on identifying the composition of watershed-derived OM to better understand inputs to inland waters and improve our ability to resolve between terrigenous and aquatic sources in downstream systems, such as estuaries and coasts. We surveyed OM sources from the Yuba River watershed in northern …
Following The Sand Grains, Duncan M. Fitzgerald, Zoe J. Hughes, Alice Staro, Christopher J. Hein, Et Al
Following The Sand Grains, Duncan M. Fitzgerald, Zoe J. Hughes, Alice Staro, Christopher J. Hein, Et Al
VIMS Articles
When longshore transport systems encounter tidal inlets, complex mechanisms are involved in bypassing sand to downdrift barriers. Here, this process is examined at Plum Island Sound and Essex Inlets, Massachusetts, USA. One major finding from this study is that sand is transferred along the coast—especially at tidal inlets—by parcels, in discrete steps, and over decadal-scale periods. The southerly orientation of the main-ebb channel at Plum Island Sound, coupled with the landward migration of bars from the ebb delta to the central portion of the downdrift Castle Neck barrier island, have formed a beach protuberance. During the constructional phase, sand is …
A Cycle Of Wind-Driven Canyon Upwelling And Downwelling At Wilmington Canyon And The Evolution Of Canyon-Upwelled Dense Water On The Mab Shelf, Haixing Wang, Donglai Gong, Marjorie A.M. Friedrichs, Courtney K. Harris, Travis Miles, Hao-Cheng Yu, Yinglong J. Zhang
A Cycle Of Wind-Driven Canyon Upwelling And Downwelling At Wilmington Canyon And The Evolution Of Canyon-Upwelled Dense Water On The Mab Shelf, Haixing Wang, Donglai Gong, Marjorie A.M. Friedrichs, Courtney K. Harris, Travis Miles, Hao-Cheng Yu, Yinglong J. Zhang
VIMS Articles
Submarine canyons provide a conduit for shelf-slope exchange via topographically induced processes such as upwelling and downwelling. These processes in the Wilmington Canyon, located along the shelf-break of the Mid-Atlantic Bight (MAB), have not been previously studied, and the associated hydrographic variability inside the canyon and on the adjacent shelf are largely unknown. Observations from an underwater glider deployed in Wilmington Canyon (February 27 - March 8, 2016), along with wind and satellite altimetry data, showed evidence for a wind-driven canyon upwelling event followed by a subsequent downwelling event. Next, a numerical model of the MAB was developed to more …
Spreading And Accumulation Of River-Borne Sediments In The Coastal Ocean After The Environmental Disaster At The Doce River In Brazil, Angleo T. Lemos, Alexander Osadchiev, Piero L. F. Mazzini, Et Al
Spreading And Accumulation Of River-Borne Sediments In The Coastal Ocean After The Environmental Disaster At The Doce River In Brazil, Angleo T. Lemos, Alexander Osadchiev, Piero L. F. Mazzini, Et Al
VIMS Articles
This study is focused on the fate of a large volume of mine slurry discharged from the Doce River (DR) to the coastal ocean after the worst environmental disaster in Brazilian which occurred in November 2015. We used Eulerian (ROMS) and Lagrangian (STRiPE) numerical models, as well as satellite remote sensing data, to study the spreading and seafloor accumulation of fine river-borne sediments during the initial six months following the disaster. We show that the regions of intense sediment accumulation were determined by spreading patterns of the surface-advected DR plume. The river discharge rate governed the plume surface area, while …
Status, Change, And Futures Of Zooplankton In The Southern Ocean, Nadine M. Johnston, Eugene J. Murphy, (...), Walker O. Smith Jr., Deborah K. Steinberg, Et Al
Status, Change, And Futures Of Zooplankton In The Southern Ocean, Nadine M. Johnston, Eugene J. Murphy, (...), Walker O. Smith Jr., Deborah K. Steinberg, Et Al
VIMS Articles
In the Southern Ocean, several zooplankton taxonomic groups, euphausiids, copepods, salps and pteropods, are notable because of their biomass and abundance and their roles in maintaining food webs and ecosystem structure and function, including the provision of globally important ecosystem services. These groups are consumers of microbes, primary and secondary producers, and are prey for fishes, cephalopods, seabirds, and marine mammals. In providing the link between microbes, primary production, and higher trophic levels these taxa influence energy flows, biological production and biomass, biogeochemical cycles, carbon flux and food web interactions thereby modulating the structure and functioning of ecosystems. Additionally, Antarctic …
Quantifying Seasonal Particulate Organic Carbon Concentrations And Export Potential In The Southwestern Ross Sea Using Autonomous Gliders, Meredith G. Meyer, Randolph G. Jones, Walker O. Smith Jr.
Quantifying Seasonal Particulate Organic Carbon Concentrations And Export Potential In The Southwestern Ross Sea Using Autonomous Gliders, Meredith G. Meyer, Randolph G. Jones, Walker O. Smith Jr.
VIMS Articles
To assess the temporal biological and hydrographic features of the southwestern Ross Sea, we deployed a glider in a spatially restricted, ice-free area during the austral summer (1 December–6 February), and quantified from sensor measurements the particulate organic carbon (POC; via particulate backscatter) concentrations, their changes through time, and net community production (NCP; via dissolved O2 concentrations). The POC levels could be divided into three distinct phases (I, II, and III, respectively) characterized by changes in NCP, surface-layer POC concentrations, remineralization, and export. Surface POC concentrations increased from 215 mg C m−3 in early December to a peak …
Comparison Of Electrochemical Polishing Treatments Between Phosphoric Acid And A Deep Eutectic Solvent For High-Purity Copper, Tarek M. Abdel-Fattah, Jon Derek Loftis
Comparison Of Electrochemical Polishing Treatments Between Phosphoric Acid And A Deep Eutectic Solvent For High-Purity Copper, Tarek M. Abdel-Fattah, Jon Derek Loftis
VIMS Articles
This study investigated and compared the acid-free electropolishing of copper with the state-of-the-art acidic electropolishing process. The acid-free medium used in this study is based on a deep eutectic solvent comprised of 2:1 ethylene glycol and choline chloride. The electrochemical study included voltammetry and chronoamperometry tests during the electropolishing process. The characterization techniques used were atomic force microscopy (AFM) and digital microscopy, and surface morphology comparisons summarized the electropolishing efficiency of phosphoric acid and acid-free deep eutectic solvent treatments for high-purity copper. Electropolishing copper with a deep eutectic solvent resulted in a mirror finish and a post-treatment surface that was …
The Spatio-Temporal Distribution And Transport Of Suspended Sediment In Laizhou Bay: Insights From Hydrological And Sedimentological Investigations, Bo Xie, Rui Bao, Dongxiao Yin, Et Al
The Spatio-Temporal Distribution And Transport Of Suspended Sediment In Laizhou Bay: Insights From Hydrological And Sedimentological Investigations, Bo Xie, Rui Bao, Dongxiao Yin, Et Al
VIMS Articles
Suspended sediment transport and deposition are crucial physical processes controlling the geomorphological evolution of estuaries and bays. Specially, under the context of worldwide coastal erosion, knowledge of the spatio-temporal distribution of suspended sediment concentration (SSC) and its associated sediment load have become increasingly important for bay management. However, our understanding of the mechanisms of suspended sediment dynamics continues to be hampered by the lack of high-resolution observations. Here, we present a study of the transport mechanisms and controlling factors of suspended sediment over Laizhou Bay. For this, we conducted continuous measurements of SSC, salinity, temperature, and flow velocity at nine …